Diet for my gf with Hypothyroidism

I am trying to develop a leaning diet for my girlfriend, but she suffers from an underactive thyroid. I was hoping I could get some help from anyone who knows about that type of thing, I know about diets and working out, but know nothing about diets with thyroid problems.

Her stats:
5' 4"
117lbs
25%ish bf
Working out 3-4 times a week for year and a half.

Good responder.

She has never had a diet, and just kinda eats what she wants. She has gotten in a more healty mindset, but still has the occasional junk food binges.

I wanna do her a 60% pro 20% carbs 20% fat diet, but not sure how that would affect her thyroid.

There are some studies out there that show MCT intake stimulates proper thyroid function. Soy products have also been shown to **** with the thyroid in several studies, so get her off of soy if she likes to eat soy products.

Other than that, lots of veggies man, just pile a plate full of them for her at every meal

She is being treated with it, she takes pig thyroid every day to keep her thyroid levels constant and correct. I just wanted to make sure I wasn't gonna put anything in her diet that would screw her up.